Quantitative Biodistribution of OMVs Using SPECT/CT Imaging with HYNIC-Duramycin Radiolabeling.

Area of Science:

• Microbiology
• Biotechnology
• Medical Imaging

Background:

• Bacterial outer membrane vesicles (OMVs) are crucial in host-microbiome interactions.
• OMVs show potential for vaccine development and drug delivery.
• Current methods for tracking OMV biodistribution are limited.

Purpose of the Study:

• To establish a highly efficient radiolabeling method for OMVs.
• To enable accurate in vivo biodistribution studies of OMVs.

Main Methods:

• OMVs were isolated from E. coli BL21(DE3) ΔnlpI ΔlpxM.
• Radiolabeling was performed using 99mTc-HYNIC-duramycin.
• Radiolabeling efficiency (RLE) and radiochemical purity (RCP) were assessed using HPLC.
• Biodistribution was evaluated in mice via SPECT/CT imaging.

Main Results:

• High RLE was achieved (81.84% for undiluted OMV suspension).
• Post-labeling purification yielded 100% RCP.
• Biodistribution results aligned with previous OMV tracking studies.

Conclusions:

• HYNIC-duramycin labeling offers an efficient and practical method for OMVs.
• This approach significantly improves in vivo imaging capabilities for OMVs.
• The method facilitates enhanced understanding of OMV behavior in biological systems.